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Easy-Lift Extension Ladder 



Makej Projects 



Easy-Lift Extension Ladder 

Written By: Martin Schmidt 



SUMMARY 

For me, a big drawback of extension ladders is that it usually takes a lot of effort to extend 
them to the desired height. This is partly due to the way in which they are rigged. Typically, 
the ladder is operated by a rope which is fastened to the bottom of the extending part of the 
ladder. The rope runs through a pulley at the top of the stationary part and back down to 
ground level for the operator to grasp. This simple arrangement is inexpensive to 
manufacture but it requires a force on the rope which is equal to the weight of the moving 
portion of the ladder. If the ladder is large, or if the moving parts have a high degree of 
friction, the ladder can be very difficult to extend when it is standing upright. This, in turn, 
makes it difficult to control the ladder and compromises safety. 

I recently obtained an old extension ladder for free. Its rope was missing and while I was 
measuring it to find out how much rope I needed to buy it occurred to me that I could convert 
the ladder to a double-pulley system which would make it easier and safer to use. 



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Easy-Lift Extension Ladder 

Step 1 — Analyzing the mechanism 




• In the stock extension ladder, the 
single pulley simply translates 
motion from one direction to 
another. The force required to 
extend the ladder is equal to the 
weight of the ladder's moving 
portion. 

• In a double-pulley system, 
additional motion is traded to gain 
force. The rope needs to be pulled 
twice as far, but the force required 
is equal to only half of the weight 
being lifted. 

• The second pulley will be installed 
at the bottom of the moving portion 
of the ladder. One end of the rope 
will then be fastened to the top of 
the stationary portion. The rope will 
run down the ladder and through 
the new pulley at the bottom of the 
moving portion, back up and 
through the original pulley at the 
top of the stationary portion and 
then down to the operator at ground 
level. 



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Easy-Lift Extension Ladder 



Step 2 — Parts required 




• Pulley 

• Bolt and nylock nut to fit ring on 
pulley 

• Flat washers to fit bolt 

• Metal strap 

• Rope (approximately three times 
the length of the ladder) 



Step 3 — Making the retaining strap 




• I used a strap originally designed to hold a 2" metal downspout to the wall of a house. The 
strap was exactly the length I needed. The holes in the strap had to be enlarged to 3/8" to 
accommodate the bolt. 

• Bend the strap around the bottom rung of the moving portion of the ladder. 



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Easy-Lift Extension Ladder 



Step 4 — Installing the pulley assembly 




t Put a washer on the bolt, slip the ring of the pulley between the ends of the strap and insert 
the bolt. 



• Install another washer and the nut. Tighten the assembly so that the pulley is held in an 
upright position when the ladder is stood on end. 

• Note: Make sure that the pulley does not hit the rungs on the other half of the ladder 
as the ladder is extended and retracted. Bend the strap as necessary to provide 
clearance. 







Step 5 — Installing the rope 




• Tie the rope to the top rung of the stationary portion of the ladder, next to the original 
pulley. Use a bowline knot or something similar. 

• Thread the rope between the two halves of the ladder to the bottom and run it through the 
newly-installed pulley. 

• Thread the rope along the same path back to the top of the ladder and through the original 
pulley. 



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Easy-Lift Extension Ladder 



Step 6 — Finishing the conversion 




• Run the rope down the backside of the ladder to the bottom and cut it to length. 

• If desired, leave some extra length so that you can tie the rope to the bottom rung of the 
stationary portion of the ladder. This helps keep the rope under control when you are 
moving the ladder around. 

• If you are using a synthetic rope as I did, heat-seal the end of the rope to keep it 
from unraveling. Matthew Cox has supplied this guide for sealing the end of the 
rope. 



Gr 



The rope on a stock extension ladder is often polypropylene or something similar. It is tough but 
not particularly flexible. I selected a woven nylon rope which is abrasion-resistant and very 
supple. 

After finishing the modification I stood the ladder upright and tested it. Extending the ladder was 
almost effortless. I've used it on numerous occasions since then and I'm very pleased with it. 

last generated on 2012-10-30 10:48:59 PM. 



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